SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '842e1f62cfee90524d27cab21df87ce30f631c59d6bd92008dc44db4e377bd2e' 
  AND token = 'hhM4NdZogv8F7811aNXZMJIrBcBKAlD4J4gFd3ZXAUc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}